Английский. английский для ИТ 1. Методическое пособие по совершенствованию навыков чтения и говорения на английском языке для студентов фксиС и фитиУ
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Text C Pre-reading. Match the meaning of the following English words with their Russian equivalents.
Reading. Read the text and try to guess the meaning of the words in bold. Check your variants in the dictionary. Computer Viruses Viruses are one of the biggest threats to the security of your computer files. In 1981, there was one known computer virus. Today, the count exceeds 100,000. Between 900 and 1,300 new viruses appear every month. A computer virus is a set of program instructions that attaches itself to a file, reproduces itself, and spreads to other files. The term “computer virus” is often used to refer to any malicious code or software that invades a computer system. The term malicious code (sometimes called “malware”) refers to a program or set of program instructions designed to surreptitiously enter a computer and disrupt its normal work. Many types of malicious code, including viruses, worms, and Trojan horses, are created and unleashedby individuals referred to as “hackers” or “crackers”. Viruses spread when people distribute infected files by exchanging disks and CDs, sending e-mail attachments, exchanging music on file-sharing networks, and downloading software from the Web. Many computer viruses infectfiles executed by your computer – files with extensions such as .exe, .com. or .vbs. When your computer executes an infected program, it also executes the attached virus instructions. A virus can be classified as a file virus, boot sector virus, or macro virus. A file virus infects application programs, such as games. A boot sector virus infects the system files your computer uses every time you turn it on. These viruses can cause widespread damage to your computer files and recurring problems. A macro virus infects a set of instructions called a “macro” – a miniature program that usually contains legitimate instructions to automate document and worksheet production. When you view a document containing an infectedmacro, the macro virus duplicates itself into the general macro pool, where it is picked up by other documents. In addition to replicating itself, a virus might deliver a payload, which could be as harmless as displaying an annoying message or as devastating as corrupting the data on your computer’s hard disk. A trigger event, such as a specific date, can unleash some viruses. For example, the Michelangelo virus triggers on March 6, the birthday of artist Michelangelo. A Trojan horse (sometimes simply called a “Trojan”) is a computer program that seems to perform one function while actually doing something else. Trojan horses are notorious for stealing passwords using a keylogger – a type of program that records your key-stroke. Any software that can automate a task or autonomously execute a task when commanded to do so is called an intelligent agent. Because an intelligent agent behaves somewhat like a robot, it is often called a bot. Like a spider in its web, the person who controls many bot-infested computers can link them together into a network called a botnet. Botnets as large as 400,000 computers have been discovered by security experts. Malicious Code Trends
These are the top three steps you can take to prevent your computer from becoming infected: - Use antivirus software on every computing device you own. - Keep software patches and operating system service packs up to date. - Do not open suspicious e-mail attachments. Antivirus software is a type of utility software that can look for and eradicate viruses, Trojan horses, bots, and worms. This essential software is available for handheld computers, personal computers, and servers. Popular antivirus software for personal computers includes McAfee VirusScan, Norton AntiVirus, and F-Secure Anti-Virus. Antivirus software uses several techniques to find viruses. As you know, some viruses attach themselves to an existing program. The presence of such a virus often increases the length of the original program. The earliest antivirus software simply examined the programs on a computer and recorded their length. A change in the length of a program from one computing session to the next indicated the possible presence of a virus. To counter early antivirus software, hackers became more cunning. They created viruses that insert themselves into unused portions of a program file without changing its length. Antivirus software developers fought back. They designed software that examines the bytes in an uninfected application program and calculates a checksum. A checksum is a number calculated by combining the binary values of all bytes in a file. Each time you run an application program, antivirus software calculates the checksum and compares it with the previous checksum. If any byte in the application program has changed, the checksum will be different, and the antivirus software assumes that a virus is present. Today’s viruses, Trojan horses, bots, and worms are not limited to infecting program files, so modern antivirus software attempts to locate them by searching your computer’s files and memory for virus signatures. A virus signature is a section of program code, such as a unique series of instructions, that can be used to identify a known malicious program, much as a fingerprint is used to identify an individual. Comprehension check. Choose the ending for each sentence from the two versions given.
Vocabulary practice 1. Which word does not belong to the group? a) virus, worm, Trojan horse, bot, file, botnet; b) distribute, download, automate, infect, view, execute; c) duplicates, instructions, infects, invades, behaves, spreads; d) spider, programmer, hacker, user, server, developer; e) individual, general, normal, personal, analytical, digital. 2. Fill in the blanks choosing from the variants given. 1. Does the term computer virus refer to any malicious code that … (makes up/invades) a computer system? 2. When your computer executes an infected program it … (executes/deletes) the attached virus instructions. 3. A trigger event, such as a specific date, can … (kill/destroy/unleash) some viruses. 4. Love letter is one of the … (slowest/fastest) spreading mass-mailing worms of all time. 5. Hackers created viruses that insert themselves into … (used/unused) portions of a program file without changing its length. 3. Transform the given sentences using the word(s) in brackets without any change in meaning. 1. A computer virus is a set of programs that attaches itself to a file (connecting). 2. If a document contains an infected macro, the macro virus duplicates itself into the general macro pool, where it is picked up by other documents (doubles, selected). 3. A virus might deliver a payload which could be both harmless and devastating (do no harm, corrupt). 4. Software that can automate a task when commanded to do so is called an intelligent agent (is able, is instructed). 5. A trigger event, such as a specific date, can unleash some viruses (particular, release). 6. Trojan horses are notorious for stealing passwords using a keylogger – a type of program that records your key-strokes (known, a sort). 4. Fill in the gaps in the text. A computer virus is a set of program instructions that attaches itself to a file, reproduces itself, and spreads to the other files. You might encounter several types of viruses. A virus that attaches itself to an application program, such as a game utility, is known as a ___ virus. A boot ___ virus infects the system files your computer uses every time you turn it on. A ___ virus infects a set of instructions that automates document and worksheet production. A Trojan horse is a computer program that seems to perform one function while actually doing something else. Such programs are notorious for stealing ___, although some delete files and cause other problems. ___ software can help prevent viruses from invading your computer system and can root out viruses that that take up residence. This software typically scans for a virus ___ and is sometimes referred to as virus scanning software. Speaking. Discuss the following questions. 1. What is a computer virus? 2. How do viruses spread? 3. Are there different kinds of viruses? 4. What is a Trojan horse? What is a bot? 5. What is a botnet? 6. How can you avoid viruses and worms? 7. What is antivirus software? How does it work? Text D Reading. Read the text and try to guess the meaning of the words in bold. Check your variants in the dictionary. Data Backup Backup and restore procedures Have you ever mistakenly copied an old version of a document over a new version? Has your computer's hard disk drive gone on the fritz? Did a virus wipe out your files? Has lightning “fried” your computer system? These kinds of data disasters are not rare; they happen to everyone. You can’t always prevent them, so you need a backup plan that helps you recover data that's been wiped out by operator error, viruses, or hardware failures. A backup is a copy of one or more files that has been made in case the original files become damaged. A backup is usually stored on a different storage medium from the original files. For example, you can back up files from your hard disk to a different hard disk, a writable CD or DVD: tape, floppy disk, or Web site. A good backup plan allows you to restore your computing environment to its pre-disaster state with a minimum of fuss. Unfortunately, no single backup plan fitseveryone’s computing style or budget. You must devise your own backup plan that’s tailored to your particular computing needs. A full-system backup contains a copy of every program, data, and system file on a computer. The advantage of a full-system backup is that you can easily restore your computer to its pre-disaster state simply by copying the backup files to a new hard disk. A full-system backup takes a lot of time, however, and automating the process requires a large-capacity tape backup device or a second hard disk drive. A workable alternative to a full system backup is a “selective” backup that contains only your most important data files. The disadvantage of this backup strategy is that because you backed up only data files, you must manually reinstall all your software before restoring your data files. If your strategy is to back up your important data files, the procedure can be simplified if you’ve stored all these files in one folder or its subfolders. In addition to data files you create, a few other types of data files might be important to you. Consider making backups of these-files: - Internet connection information - E-mail folders - E-mail address book - Favorite URLs - Downloads Windows users often hear a variety of rumors about backing up the Windows Registry. The Registry, as it is usually called, is an important group of files the Windows operating system uses to store configuration information about all the devices and software installed on a computer system. As simple as it sounds, backing up the Registry can present a bit of a problem because the Registry is always open while your computer is on. Windows users whose backup plans encompass all files on the hard disk must make sure their backup software provides an option for including the Windows Registry. Your backup schedule depends on how much data you can afford to lose. If you’re working on an important project, you might want to back up the project files several times a day. Under normal use, however, most people schedule a once-a-week backup. If you work with a To Do list, use it to remind yourself when it is time to make a backup. Store your backups in a safe place. Don’t keep them at your computer desk because a fire or flood that damages your computer could also wipe out your backups. Storing your backups at a different location is the best idea, but at least store them in a room apart from your computer. Backup devices The backup device you select depends on the value of your data, your current equipment, and your budget. Most computer owners use what they have — a writable CD drive, Zip drive, or floppy disk drive. The major disadvantage of backing up your data on CDs and DVDs is that the writing process is slow — slower than writing data to tape or a removable hard disk. Further, although it is feasible to back up your entire system on a series of CDs or DVDs, you would have to use special backup software, monitor the backup process, and switch disks occasionally. CDs and DVDs are more practical for backing up a select group of important data files. Zip disks with 100 MB or 250 MB capacity are sufficient for backups of documents and most digital graphics files. Several 750 MB Zip disks might be enough for backing up all your data files and could be feasible for a full-system backup if you have not installed lots of application software. A second hard disk drive is a good backup option — especially if it has equivalent capacity to your main hard disk. This capacity allows the backup process to proceed unattended because you won’t have to swap disks or CDs. Speed-wise, a hard disk is faster than tape, CD, or DVD drives. Unfortunately, like your computer’s main hard disk, a backup hard disk is susceptible to head crashes, making it one of the least reliable storage options. Network and internet backup If your computer is connected to a local area network, you might be able to use the network server as a backup device. Before entrusting your data to a server, check with the network administrator to makesure you are allowed to store a large amount of data on the server. Because you might not want strangers to access your data, you should store it in a password-protected, non-shared folder. You also should makesure the server will be backed up on a regular basis so that your backup data won’t be wiped out by a server crash. Several Web sites offer fee-based backup storage space. When needed, you can simply download backup files from the Web site to your hard disk. These sites are practical for backups of your data files, but space limitations and download times make them impractical for a full-system backup. Experts suggest that you should not rely on a Web site as your only method of backup. If a site goes out of business or is the target of a Denial of Service attack, your backup data might not be accessible. Backup software To make a backup, you can use backup software — a set of utility programs designed to back up and restore files. Backup software usually includes options that make it easy to schedule periodic backups, define a set of files that you want to regularly back up, and automate the restoration process. Backup software differs from most copy routines because it typically compresses all the files for a backup and places them in one large file. Under the direction of backup software, this file can spread across multiple tapes if necessary. The file is indexed so that individual files can be located, uncompressed, and restored. Boot disks A boot disk is a floppy disk or CD containing the operating system files needed to boot your computer without accessing the hard disk. A barebones boot disk simply loads the operating system kernel. It is needed, if your hard disk fails or a virus wipes out the boot sector files on your hard disk, you will not be able to use your normal bootprocedure. To create an MS-DOS boot disk, insert a blank floppy disk in drive A. Open My Computer or Windows Explorer, and then right-click the Drive A icon. Select Format and check the box labeled Create an MS-DOS startup disk. Сomprehension check. Match the beginnings of the sentences in the first column with the endings in the second one.
Vocabulary practice 1. Put the appropriate unscrambled words into the sentences on the right.
2. Fill in the blanks choosing from the variants given. 1. A backup is usually … (detected/stored) on a different storage medium from the original files. 2. A workable alternative to a full system backup is a … (selective/overall) backup that contains only your most important data files. 3. Storing your backups at a different locations is … (not a good/the best) idea. 4. The backup device you select depends on … (how much data you can afford to lose/the value of your data/your current equipment and your budget). 5. A full-system backup … (can be done in no time/takes a lot of time). 6. Under normal use most people schedule … (an everyday backup/once-a-week backup). 3. Match the beginnings and the endings of the instructions/steps given and put them into correct order.
4. Fill in the gaps in the text. A backup is a copy of one or more files that has been made in case the original files become damaged. For safety, a backup is usually stored on a different storage medium from the original files. A good backup plan allows you to ___ your computing environment to its pre-disaster state with a minimum of fuss. No single backup plan fits everyone’s computing style or budget. Your personal backup plan depends on the files you need to back up, the hardware you have available to make backups, and your backup software. In any case, it is a good idea to back up the Windows ___ and make sure your files are free of ___. Backups should be stored in a safe place, away from the computer. Backups can be recorded on floppy disks, writable CDs and DVDs, networks, Web sites, a second hard disk, or tapes. Many computer owners depend on writable CDs for backups, and use My Computer or Windows ___ to simply select files and copy files to the backup. ___ drives and backup software are typically used in business situations when a full-system backup is desirable. Backup software differs from most copy routines because it ___ all the files for a backup into one large file. In addition to file backups, you should have a ___ disk containing the operating system files and settings needed to start your computer without accessing the hard disk. Speaking. Discuss the following questions. 1. Why do you need to make backups? 2. What are the major strategies and plans of backup? What does their choice depend on? 3. What are the advantages and disadvantages of different backup devices? 4. What can you say about network and internet backup? 5. What can you say about backup software? 6. What is a boot disk? How can it be created? Critical thinking. Read the article and express you opinion on the problem. |